I'm taking a caricature course over at Schoolism.com. Every week I get a lecture and an assignment that has to be handed in, which I get a personal critique from the teacher (Jason Seiler). It has been really great so far, I feel I'm learning a lot for every assignemt. The lectures are great too, highly recommended.
Here's some of the drawings I've handed in so far:
(Some better than others, but that's hopefully a good thing :)